OSI/MHS Configuration and Management Manual

OSI Address Configuration in OSI/MHS
OSI/MHS Configuration and Management Manual—424827-003
D-17
Advanced Addressing Configurations
Remote NSAP
The #NSAP entry for the REM-NSAP-1 parameter of the ADD MTA command (<in-s-
nsap>) defines a #L4 profile and a #L3 profile.
The #L3 profile defines the X.25 NUA of the adjacent MTA and also the subaddress
that will be used in the X.25 calling address for outgoing connections. Note that, in this
example, the port number used here is the same as the port number in the #L3 profile
of the local configuration (see Local MR Group Address Configuration on page D-13),
so IN(D) and OUT(S) have the same value.
It should be remembered that the REM-NSAP-n parameter is used to validate
incoming associations from adjacent MTAs. Since no NSAP values are carried in
X.25(1980) networks, an NSAP value is generated by converting the calling X.25 NUA
into a hexadecimal string. This means that REM-NSAP-n parameters must be
configured as hexadecimal representations of the remote MTA’s calling NUA (<in-s-
nsap>).
The Complete Set of Addresses
The example has now established all the definitions required for the address
components needed to set up connections between OSI/MHS and the adjacent MTA.
Here is the complete set of addresses defined by these commands:
OUT(D): t-selector = 4D4853415431
X.25 NUA = 311042100091206
IN(S): t-selector = 4D4853415431
X.25 NUA = 311042100091206
OUT(S): t-selector = 313131
X.25 NUA = 23422350016101
IN(D): t-selector = 313131
X.25 NUA = 23422350016101
Advanced Addressing Configurations
The above example is one of the simplest possible for a connection between an
OSI/MHS subsystem and an adjacent MTA. The following subsections discuss some
variations that support more complex configurations.
Defining a Different Outgoing Calling Address
In the above example, IN(D) is the same as OUT(S). One of the simplest changes to
make is to define a different <out-s-nsap>. When the 1980 version of X.25 is used,
this can be done by changing the port number on the #L3 profile for the adjacent MTA
(See Adjacent MTA Address Configuration on page D-15).